A positive displacement rotary machine (PDRM) (RU 2004133654) having a body with an internal ring cavity is known. A spiral separator with a rotor inside is installed in this cavity. The rotor working surface is a surface of rotation, where there is at least one slot along the rotation axis of the rotor, in each of which a piston partly extending (projecting) from one side of the rotor is rotatably mounted. Besides, the piston has at least one through-slot across its perimeter interacting with the separator for the piston and the rotor rotation synchronization. The machine inlet and outlet openings are spaced along the rotor axis and separated from each other by the separator.
Such machine has the following advantages.
The piston is securely installed in the rotor slot extending from it for about a halfway. The inlet and outlet openings spacing configuration along the rotor axis facilitates combination of such machines into multistage machines including those with a common rotor for multiple stages. Such machines are used in submersible units. The common rotor enables the reduction of radial load and often thrust load on the bearings of the rotor by balancing the loads on the individual stages in case the stages are turned relative to each other.
An essential advantage of the pump, produced on the basis of this machine, is the uniform flow rate.
Disadvantage of such machines is a complicated configuration of the separator and the piston slot that does not allow contact between them over a large area in order to reduce wear of the friction pair (to reduce an ideal load on the friction pair and extend its service life).
A PDRM is known (GB 1458459 and similar to it DE 3206286 A1), the body of which contains a cavity in the form of a spherical segment, in which a separator is installed along the axis of symmetry of the cavity shaped as a sector of a circle closing off the cavity; a rotor installed inside the body and capable of rotation has the working surface in the form of two truncated cones resting with their tops on a sphere from the opposite sides, while on the surface of the sphere, at an angle to the axis of symmetry of the rotor, there is a circular groove positioned tangentially with respect to both cones. A piston with a through-slot, allowing the passing through of the separator, is rotatably mounted in this groove. The piston interacts with the separator through a sealing synchronizing element (SSE), embodied in the form of a cylinder sectioned in half by a through-slot, which begins at one end and extends most of the way to the other end. The working medium inlet opening and corresponding outlet opening are located on the same side of the piston. On the other side of the piston there is one more pair of inlet and outlet openings.
Such a machine has the following advantages: a good contact of the piston with the body chamber along the spherical surface, a good contact between the piston, the sealing element and the separator, simple geometrical forms: the flat separator, the flat piston and others.
PDRM also has disadvantages: the difficulty of combining such a machine into a multi-stage machine, associated with the fact that the inlet and outlet openings are located on the same side of the piston, and in order to get from one stage to another, a channel is required bypassing the spherical cavity of the body along the rotor axis. Also considered as disadvantages are: non-uniform flow rate, weak mounting of the piston (which is only partially located inside the groove on the sphere), which also weakens the shaft due to the circular groove, unreliable mounting of the sealing synchronizing element in the slot of the piston (jamming is possible under increased loads).
The PDRM (DE 3146782 A1), having a body with a cavity in the form of spherical segment and a rotatably mounted rotor with through-slot along the rotor axis, is known. There is also a piston in the form of a disk rotatably mounted in the rotor slot, a chamber in the form of spherical segment partitioned by a separator in the direction of the rotor rotation as well as outlet and inlet openings located in front of and behind the separator accordingly. Besides, the piston rotation is synchronized with the rotor rotation by means of a shaft, fixedly going through the rotor, and the system of gears, one of which is fixed at the piston.
Advantages of this machine include spherical contact between the piston and the chamber, reliable mounting of the piston extending towards both sides from the shaft, presence of a strong shaft (longitudinal slot barely weakens it), possibility to arrange (to space) the inlet and outlet openings along the shaft to combine several stages on one shaft, independence of leaks on the wear of synchronizing mechanism, and possibility of high rotation speed.
Unreliable synchronizing mechanism, especially in case if the gear shaft is required to pass through several stages, is referred to as disadvantage.
A positive displacement rotary machine (application RU 2006119356), comprising a body, working surface of which is made in the form of a spherical segment part; a rotor rotatably mounted in the body and having a working surface of rotation; a ring concentric working cavity formed by the body and the rotor; a separator in the form of the inclined washer, geometrical axis of which is inclined to the geometrical axis of the rotor rotation, fixedly mounted in the body and dividing the working cavity into two parts, is known; besides at least one slot is made on the rotor working surface along its geometrical axis of rotation; a piston, which can close off (seal) the working cavity and oscillate rotationally about its geometrical axis intersecting geometrical axis of the rotor, is mounted in the rotor; moreover, the piston is made at least in the form of a part of a disk and there is at least one sealing through-slot for the separator passage in each piston.
The advantages of this machine are spherical contact of the piston and the chamber, reliable fastening of the piston extending from the shaft in both sides, the strength shaft availability (the longitudinal slot looses it a little), the reliable piston synchronization, the good piston sealing.
The PDRM also has the following disadvantages: difficulty of combining such a machine into a multistage machine associated with the fact that corresponding the inlet and outlet openings are located on the same side of the separator; therefore it is necessary to make a duct going around the body spherical cavity along the rotor axis for passing from stage to stage. Non-uniform flow rate, contributing to difficulty of combining into a multistage machine, is also referred to as disadvantage.
The object of this invention is to develop a positive displacement high-speed rotary machine of high tightness with strength shaft, reliable fastening of the displacement element (the piston), the reliable synchronizing mechanism, allowing multiple short-time overloads, long service life and low inertial loads from the piston side on the synchronizing mechanism. These features allow using the machine in multistage submersible pumps, producing high pressure and having a large margin of strength, as well as give possibility of restarting after a sustained interruption or short-time changes of working medium properties (for example, solidification).
Besides, the machine shall have good specific characteristics: large flow rate at a specified overall diameter, high working pressure per a stage, large margin of strength at short-time pressure increase per a stage, long service life due to both design and possibility of using wear-resistant materials in it.
The desired effect can be achieved due to making through-holes, for working medium flowing to the other separator side, at one of the separator areas (for example, the descending area) in the machine according to application RU 2006119356. In that case, the working medium inlet and outlet openings can be made in the body under and above the ascending area of the separator that is favorable for a multistage machine. Besides, the flow rate (displacement) of such machine becomes almost uniform. Moreover, the separator area with through-passes to the other side continues to seal the piston slot (or SSE slot if it is used) and participate in the piston synchronization.
The assigned task is achieved due to the fact that according to the invention, the positive displacement rotary machine comprising the body, working surface of which is embodied in the form of a part of segment of a torus; a rotor with a working surface of rotation, rotatably mounted in the body; a ring working cavity, formed by the working surfaces of the body and the rotor; a separator in the form of a washer, fixedly mounted in the body and dividing the working cavity at an angle to the plane of the rotor rotation into two parts; where the separator has two conditional areas, the ascending and descending areas, with approximate boundary at the two opposite separator points, located along the rotor axis at a maximum distance from each other; moreover at least one slot is made on the rotor working surface along its geometrical axis of rotation and the piston, which can close off (seal) the working cavity and oscillate rotationally in the plane of the slot, is mounted in each slot of the rotor; besides, the piston is made at least in the form of a part of a disk and there is at least one sealing through-slot for the separator in each piston, is characterized in that at least one through-pass is made at one of the separator parts (at the descending area) to enable a working medium flow from one side of the separator to the other.
According to the invention, the body working surface is made in the form of a spherical segment (the sphere is a particular case of torus, the circular axis radius of which is equal to zero).
According to the invention, the working medium inlet and outlet openings are made at bypass part of the body, under and above the ascending part of the separator accordingly.
According to the invention, the rotor working surface is made in the form of two coaxial surfaces of truncated cones rested with their truncated parts against the sphere.
The assigned task is also achieved due to the fact that according to the invention, the slots on the rotor working surface are connected at the center of the rotor.
The assigned task is also achieved due to the fact that according to the invention, the separator is made in the form of the flat washer.
The assigned task is also achieved due to the fact that according to the invention, the separator is made in the form of a washer with a conical working surface.
The assigned task is also achieved due to the fact that according to the invention, the separator is mounted in the body so that its diametrically opposite parts, located from the opposite sides, is in contact with the rotor.
The assigned task is also achieved due to the fact that according to the invention, recesses are made on the separator at places of contact with the rotor.
The assigned task is also achieved due to the fact that according to the invention, the separator is made in the form of two parts of the washer.
The assigned task is also achieved due to the fact that according to the invention, the washer parts are connected using a “>” type joint (connection).
The assigned task is also achieved due to the fact that according to the invention, the piston is made in the form of a disk with a spherical side surface and two through-slots for the separator.
The assigned task is also achieved due to the fact that according to the invention, the piston is made in the form of the disk with two through-slots for the separator, having weight decrease hollows at the area distant from the slots.
The assigned task is also achieved due to the fact that according to the invention, the piston is made in the form of a truncated disk sector with an angle of less than 180 degrees having one through-slot for the separator.
The assigned task is also achieved due to the fact that according to the invention at least one sealing synchronizing element is mounted in the piston through-slot.
The assigned task is also achieved due to the fact that according to the invention, the sealing synchronizing element is made in the form of a cylinder with through-slots at its ends; besides, the slot planes coincide.
The assigned task is also achieved due to the fact that according to the invention, the piston slot side surfaces are enlarged by means of projections.
The assigned task is also achieved due to the fact that according to the invention, the central part of the sealing synchronizing element is of less diameter.
The assigned task is also achieved due to the fact that according to the invention, the sealing synchronizing element is made in the form of the overlays for the piston slot.
The assigned task is also achieved due to the fact that according to the invention, the sealing synchronizing element is made in the form of two plates, connected by means of the shaft.
The assigned task is also achieved due to the fact that according to the invention, the sealing synchronizing element is made in the form of a roller.
According to the invention at least one pass is made at an angle to the separator geometrical axis.
According to the invention, the machine is made as multistage; besides, the rotor is made as common for all the stages.
According to the invention, ducts for turning the working medium flow around the rotor are made in the body after the first stage and further at intervals of two stages.
The similar elements are designated by the same numbers on all the figures, where:    1—the body;    2—the body part, ascending half;    3—the body part, descending half;    4—the spherical cavity;    5—the concentric hole for the rotor shaft output;    6—the machine geometrical axis;    7—the rotor;    8—the piston;    9—the separator;    10—the ascending (bypass) part of the separator;    11—the descending (discharge) part of the separator;    12—the inlet opening;    13—the outlet opening;    14—the duct without flow turning around the body;    15—the duct for flow turning around the body;    16—the spherical part of the rotor above the cone;    17—the rotor surface in the form of truncated cone;    18—the central spherical part of the rotor;    19—the rotor shaft output;    20—the working chamber;    21—the slot in the rotor for the piston;    22—the cutout in the rotor for the piston shaft;    23—the recess in the rotor for SSE;    24—the spherical surface of the body;    25—the flat (conic) surface of the separator;    26—the piston geometrical axis;    27—the piston shaft;    28—the piston outer part;    29—the piston central thickened part;    30—the piston through-hole for SSE;    31—the piston spherical side surface;    32—the piston spherical transition part;    33—the piston through-slot for the separator;    34—the recess for the roller in the piston through-slot;    35—the piston through-slot bottom;    36—the piston through-slot side surface;    37—the cylinder on the side surface of the piston through-slot;    38—the cylindrical recess on the side surface of the piston through-slot;    39—the cylindrical hole in the piston to accommodate SSE;    40—the separator joint;    41—the inner spherical surface of the separator;    42—the through-pass in the separator;    43—the separator legs;    44—the sealing synchronizing element (SSE);    45—the SSE through-slot to accommodate the separator;    46—the SSE projections;    47—the pin;    48—the flat or cone-shaped area on the SSE;    49—the side surface of the SSE slot;    50—the bottom of the SSE slot;    51—the SSE spherical end;    52—the SSE cylindrical projection;    53—the SSE cylindrical recess;    54—the SSE plates;    55—the shaft connecting the SSE plates;    56—the roller mounted into the piston slot;    57—the piston weight decrease hollows;    58—a half of the “scissors” type piston;    59—the piston cutout;    60—the cylindrical part of the SSE;    61—the SSE cutout for an articulated cross joint;    62—the hole in the SSE cutout for mounting the axle of the articulated cross;    63—the minimum specific part, 1-st half;    64—the minimum specific part, 2-d half;    65—the area of the slit rotor;    66—the four-stage machine body, 1-st half;    67—the four-stage machine body, 2-d half.